The present invention relates to dentistry in general, and more particularly to an improved dental anchor for building superstructures on broken or undermined dentition.
Anchoring a superstructure to the understructure of a tooth usually requires drilling a number of channels into the tooth or understructure. Depending upon the tooth involved, one or more anchoring rods are then secured in the channels and are allowed to protrude above the understructure with the exposed or protruding portions of the rods serving to anchor the superstructure. It should be noted, that in this type of dental operation, these rods are extremely small, for example, being on the order of 0.03" in diameter and approximately 0.20" in length.
The rods are retained in the channels by (1) cementation, by (2) being screwed into the channels, or by (3) friction lock where the rod is forced into a channel of smaller diameter. According to tensile tests performed on rods secured in dentin, self-threading rods have the greatest retention of the three types tested, where the friction lock is classified as intermediate, and the cemented rod is the least retentive.
It is noted, that prior art dental anchors are disclosed in my U.S. Pat. No. 3,434,209 showing a structure of a single dental anchor, and my U.S. Pat. No. 3,675,328 showing two dental anchors interconnected to one another which are readily severable from one another.
It is noted, that stresses are normally present when inserting the prior art dental anchors into the channels. Additionally, the construction of the prior art dental anchors require torque for insertion thereof into the channels provided in the tooth.